<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>

</head>
<body>
    <div id="app">
        <p>{{a}}</p>
    </div>
    <script>
        var data={
            a:1,
        };
        // 冻结属性
        Object.freeze(data);
        var app =new Vue({
            el:"#app",
            data
        });
    </script>
</body>
</html>